Feature-based interaction: an identification and classification methodology

Features are an established means of adding non-geometric information and extra geometric semantics to conventional computer aided design (CAD) systems. For some time it has been realized that, although feature-based modelling is necessary for the next generation of integrated design and manufacturing systems, the inherent feature interactions pose a difficulty in representing and manipulating geometric designs. This paper presents a structured geometric spatial feature interaction identification method based on a broad multilevel classification. Feature interaction definitions and classifications have been surveyed and it is evident that, although many feature interaction classifications have been proposed, there is a lack of a general framework. The classification presented here encompasses existing feature interference cases found in the literature and defines a singular framework that leads to a general classification structure. The framework is presented and applied at three different levels and each interaction case is defined by feature parameters rather than just geometric entities. The restrictions often found in other research concerning contact:non-contact and concave:convex situations are avoided. The resulting classification is easy to understand and implement because it uses simple rules based on commonly available Boolean operators. Finally, an example component is presented and the advantages, uses and applications of the classification scheme are discussed.